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Residents on the Upper East Side have new concerns about the ongoing construction. But are they really at risk? Andrew Siff reports. (Published Monday, Mar 19, 2012)

Updated at 1:46 PM EDT on Tuesday, Mar 20, 2012

An air sample taken underground at the Second Avenue subway construction site had excessive levels of a dangerous dust particle, a federal safety inspection has found.

The sample was taken by the Occupational Safety and Health Administration on Nov. 9. The agency's report, which found the sample contained more than three times the allowable level of toxic dust particles called silica, was released last week to Assemblyman Micah Kellner.

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Those exposed to excessive levels of silica may develop silicosis, an incurable, sometimes deadly lung condition common among construction workers.

"I'm very concerned," said Christine Seketa, who lives near the construction site. "I have a baby. They're drilling stuff up, I'd like to know what the health implications are."

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OSHA called the silica levels in the tunnel a "serious" safety violation and fined three contractors on the site. The contractors have until April 20 to appeal.

Despite the test sample findings, the MTA tells NBC New York that the levels of silica found underground in the preliminary findings "under no circumstance impacts air quality at street level.''

Spokesman Kevin Ortiz said "silica does not float in the air, but rather drops to the ground, so it is essentially impossible for it to impact the air quality at the street level 100 feet above.''

But some people who live and work in the area remain skeptical.

"My office is two doors down, and I don't really trust the people who give out the information in terms of the safety of people who live here," said Robert Allen, who works on the Upper East Side.

Residents in the neighborhood have long complained about the air quality around the site. Many claim to have developed respiratory problems because of their proximity to the construction zone, dubbing them the "Second Avenue Cough."

In January, a top MTA executive said the agency had performed rigorous tests and found no toxic chemicals above EPA standards. The agency has insisted there is no threat to public health.

The Second Avenue subway line will be 1.7 miles long. It's due to open in 2016.

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